Unitary Quick Connect Prosthetic Heart Valve and Deployment System and Methods

ABSTRACT

A quick-connect heart valve prosthesis that can be quickly and easily implanted during a surgical procedure is provided. The heart valve includes a substantially non-expandable, non-compressible prosthetic valve and a plastically-expandable coupling stent, thereby enabling attachment to the annulus without sutures. A small number of guide sutures may be provided for aortic valve orientation. The prosthetic valve may be a commercially available valve with a sewing ring with the coupling stent attached thereto. The coupling stent may expand from a conical deployment shape to a conical expanded shape, and may include web-like struts connected between axially-extending posts. A system and method for deployment includes a hollow two-piece handle through which a balloon catheter passes. A valve holder is stored with the heart valve and the handle easily attaches thereto to improve valve preparation steps.

RELATED APPLICATION

This application claims priority to U.S. Provisional Application No.61/220,968, filed Jun. 26, 2009, the entire disclosure of which isincorporated by reference herewith.

FIELD OF THE INVENTION

The present invention generally relates to prosthetic valves forimplantation in body channels. More particularly, the present inventionrelates to unitary prosthetic heart valves configured to be surgicallyimplanted in less time than current valves.

BACKGROUND OF THE INVENTION

In vertebrate animals, the heart is a hollow muscular organ having fourpumping chambers as seen in FIG. 1—the left and right atria and the leftand right ventricles, each provided with its own one-way valve. Thenatural heart valves are identified as the aortic, mitral (or bicuspid),tricuspid and pulmonary, and are each mounted in an annulus comprisingdense fibrous rings attached either directly or indirectly to the atrialand ventricular muscle fibers. Each annulus defines a flow orifice.

The atria are the blood-receiving chambers, which pump blood into theventricles. The ventricles are the blood-discharging chambers. A wallcomposed of fibrous and muscular parts, called the interatrial septumseparates the right and left atria (see FIGS. 2 to 4). The fibrousinteratrial septum is a materially stronger tissue structure compared tothe more friable muscle tissue of the heart. An anatomic landmark on theinteratrial septum is an oval, thumbprint sized depression called theoval fossa, or fossa ovalis (shown in FIG. 4).

The synchronous pumping actions of the left and right sides of the heartconstitute the cardiac cycle. The cycle begins with a period ofventricular relaxation, called ventricular diastole. The cycle ends witha period of ventricular contraction, called ventricular systole. Thefour valves (see FIGS. 2 and 3) ensure that blood does not flow in thewrong direction during the cardiac cycle; that is, to ensure that theblood does not back flow from the ventricles into the correspondingatria, or back flow from the arteries into the corresponding ventricles.The mitral valve is between the left atrium and the left ventricle, thetricuspid valve between the right atrium and the right ventricle, thepulmonary valve is at the opening of the pulmonary artery, and theaortic valve is at the opening of the aorta.

FIGS. 2 and 3 show the anterior (A) portion of the mitral valve annulusabutting the non-coronary leaflet of the aortic valve. The mitral valveannulus is in the vicinity of the circumflex branch of the left coronaryartery, and the posterior (P) side is near the coronary sinus and itstributaries.

The mitral and tricuspid valves are defined by fibrous rings ofcollagen, each called an annulus, which forms a part of the fibrousskeleton of the heart. The annulus provides peripheral attachments forthe two cusps or leaflets of the mitral valve (called the anterior andposterior cusps) and the three cusps or leaflets of the tricuspid valve.The free edges of the leaflets connect to chordae tendineae from morethan one papillary muscle, as seen in FIG. 1. In a healthy heart, thesemuscles and their tendinous chords support the mitral and tricuspidvalves, allowing the leaflets to resist the high pressure developedduring contractions (pumping) of the left and right ventricles.

When the left ventricle contracts after filling with blood from the leftatrium, the walls of the ventricle move inward and release some of thetension from the papillary muscle and chords. The blood pushed upagainst the under-surface of the mitral leaflets causes them to risetoward the annulus plane of the mitral valve. As they progress towardthe annulus, the leading edges of the anterior and posterior leafletcome together forming a seal and closing the valve. In the healthyheart, leaflet coaptation occurs near the plane of the mitral annulus.The blood continues to be pressurized in the left ventricle until it isejected into the aorta. Contraction of the papillary muscles issimultaneous with the contraction of the ventricle and serves to keephealthy valve leaflets tightly shut at peak contraction pressuresexerted by the ventricle.

Various surgical techniques may be used to repair a diseased or damagedvalve. In a valve replacement operation, the damaged leaflets areexcised and the annulus sculpted to receive a replacement valve. Due toaortic stenosis and other heart valve diseases, thousands of patientsundergo surgery each year wherein the defective native heart valve isreplaced by a prosthetic valve, either bioprosthetic or mechanical.Another less drastic method for treating defective valves is throughrepair or reconstruction, which is typically used on minimally calcifiedvalves. The problem with surgical therapy is the significant insult itimposes on these chronically ill patients with high morbidity andmortality rates associated with surgical repair.

When the valve is replaced, surgical implantation of the prostheticvalve typically requires an open-chest surgery during which the heart isstopped and patient placed on cardiopulmonary bypass (a so-called“heart-lung machine”). In one common surgical procedure, the diseasednative valve leaflets are excised and a prosthetic valve is sutured tothe surrounding tissue at the valve annulus. Because of the traumaassociated with the procedure and the attendant duration ofextracorporeal blood circulation, some patients do not survive thesurgical procedure or die shortly thereafter. It is well known that therisk to the patient increases with the amount of time required onextracorporeal circulation. Due to these risks, a substantial number ofpatients with defective valves are deemed inoperable because theircondition is too frail to withstand the procedure. By some estimates,about 30 to 50% of the subjects suffering from aortic stenosis who areolder than 80 years cannot be operated on for aortic valve replacement.

Because of the drawbacks associated with conventional open-heartsurgery, percutaneous and minimally-invasive surgical approaches aregarnering intense attention. In one technique, a prosthetic valve isconfigured to be implanted in a much less invasive procedure by way ofcatheterization. For instance, U.S. Pat. No. 5,411,552 to Andersen etal. describes a collapsible valve percutaneously introduced in acompressed state through a catheter and expanded in the desired positionby balloon inflation. Although these remote implantation techniques haveshown great promise for treating certain patients, replacing a valve viasurgical intervention is still the preferred treatment procedure. Onehurdle to the acceptance of remote implantation is resistance fromdoctors who are understandably anxious about converting from aneffective, if imperfect, regimen to a novel approach that promises greatoutcomes but is relatively foreign. In conjunction with theunderstandable caution exercised by surgeons in switching to newtechniques of heart valve replacement, regulatory bodies around theworld are moving slowly as well. Numerous successful clinical trials andfollow-up studies are in process, but much more experience with thesenew technologies will be required before they are completely accepted.

Accordingly, there is a need for an improved device and associatedmethod of use wherein a prosthetic valve can be surgically implanted ina body channel in a more efficient procedure that reduces the timerequired on extracorporeal circulation. It is desirable that such adevice and method be capable of helping patients with defective valvesthat are deemed inoperable because their condition is too frail towithstand a lengthy conventional surgical procedure.

Furthermore, surgeons relate that one of the most difficult tasks whenattempting minimally invasive heart valve implantation or implantationthrough a small incision is tying the suture knots that hold the valvein position. A typical aortic valve implant utilizes 12-24 sutures(commonly 15) distributed evenly around and manually tied on one side ofthe sewing ring. The knots directly behind the commissure posts areparticularly challenging because of space constraints. Eliminating theneed to tie suture knots or even reducing the number of knots to thosethat are more accessible would greatly facilitate the use of smallerincisions that reduces infection risk, reduces the need for bloodtransfusions and allows more rapid recovery compared to patients whosevalves are implanted through the full sternotomy commonly used for heartvalve implantation.

The present invention addresses these needs and others.

SUMMARY OF THE INVENTION

Various embodiments of the present application provide prosthetic valvesand methods of use for replacing a defective native valve in a humanheart. Certain embodiments are particularly well adapted for use in asurgical procedure for quickly and easily replacing a heart valve whileminimizing time using extracorporeal circulation (i.e., bypass pump).

In one embodiment, a method for treating a native aortic valve in ahuman heart to replaces the function of the aortic valve, comprises: 1)accessing a native valve through an opening in a chest; 2) placingguiding sutures in the annulus 3) advancing a heart valve within a lumenof the annulus; and 4) plastically expanding a metallic coupling stenton the heart valve to mechanically couple to the annulus in a quick andefficient manner.

The native valve leaflets may be removed before delivering theprosthetic valve. Alternatively, the native leaflets may be left inplace to reduce surgery time and to provide a stable base for fixing thecoupling stent within the native valve. In one advantage of this method,the native leaflets recoil inward to enhance the fixation of themetallic coupling stent in the body channel. When the native leafletsare left in place, a balloon or other expansion member may be used topush the valve leaflets out of the way and thereby dilate the nativevalve before implantation of the coupling stent. The native annulus maybe dilated between 1.0-5 mm from their initial orifice size toaccommodate a larger sized prosthetic valve.

In accordance with a preferred aspect, a heart valve includes aprosthetic valve defining therein a non-expandable, non-collapsibleorifice, and an expandable coupling stent extending from an inflow endthereof. The coupling stent has a contracted state for delivery to animplant position and an expanded state configured for outward connectionto the base stent. Desirably, the coupling stent is plasticallyexpandable.

In another aspect, a prosthetic heart valve for implant at a heart valveannulus, comprises:

-   -   a. a non-expandable, non-collapsible annular support structure        defining a flow orifice, the support structure including a        plurality of commissure posts projecting in an outflow        direction;    -   b. flexible leaflets attached to the support structure and        commissure posts and mounted to alternately open and close        across the flow orifice;    -   c. a suture-permeable ring circumscribing an inflow end of the        support structure; and    -   d. a plastically-expandable coupling stent having a first end        extending around and connected at the inflow end of the support        structure, the coupling stent having a second end projecting in        the inflow direction away from the valve support structure and        being capable of assuming a contracted state for delivery to an        implant position and an expanded state wider than the first end        for outward contact with an annulus.

In one embodiment, the heart valve comprises a commercially availableprosthetic valve having a sewing ring, and the coupling stent attachesto the sewing ring. The contracted state of the coupling stent may beconical, tapering down in a distal direction. The coupling stentpreferably comprises a plurality of radially expandable struts at leastsome of which are arranged in rows, wherein the distalmost row has thegreatest capacity for expansion from the contracted state to theexpanded state.

A method of delivery and implant of a prosthetic heart valve system isalso disclosed herein, comprising the steps of:

-   -   providing a heart valve including a prosthetic valve having a        non-expandable, non-collapsible orifice, the heart valve further        including an expandable coupling stent extending from an inflow        end thereof, the coupling stent having a contracted state for        delivery to an implant position and an expanded state configured        for outward connection to the annulus;    -   advancing the heart valve with the coupling stent in its        contracted state to an implant position adjacent the annulus;        and    -   plastically expanding the coupling stent to the expanded state        in contact with and connected to the annulus.

One embodiment of the method further includes mounting the heart valveon a holder having a proximal hub and lumen therethrough. The holdermounts on the distal end of a handle having a lumen therethrough, andthe method including passing a balloon catheter through the lumen of thehandle and the holder and within the heart valve, and inflating aballoon on the balloon catheter to expand the coupling stent. The heartvalve mounted on the holder may be packaged separately from the handleand the balloon catheter. Desirably, the contracted state of thecoupling stent is conical, and the balloon on the balloon catheter has alarger distal expanded end than its proximal expanded end so as to applygreater expansion deflection to the coupling stent than to theprosthetic valve.

In the method where the coupling stent is conical, the coupling stentmay comprise a plurality of radially expandable struts at least some ofwhich are arranged in rows, wherein the row farthest from the prostheticvalve has the greatest capacity for expansion from the contracted stateto the expanded state.

The method may employ a coupling stent with a plurality of radiallyexpandable struts, wherein a row farthest from the prosthetic valve hasalternating peaks and valleys. The distal end of the coupling stent thusexpands more than the rest of the coupling stent so that the peaks inthe row farthest from the prosthetic valve project outward intoapertures in the base stent.

Another aspect described herein is a system for delivering a heart valveincluding a prosthetic valve having a non-expandable, non-collapsibleorifice, and an expandable coupling stent extending from an inflow endthereof, the coupling stent having a contracted state for delivery to animplant position and an expanded state. The delivery system includes avalve holder connected to a proximal end of the heart valve, a ballooncatheter having a balloon, and a handle configured to attach to aproximal end of the valve holder and having a lumen for passage of thecatheter, wherein the balloon extends distally through the handle, pastthe holder and through the heart valve. In the system, the prostheticvalve is preferably a commercially available valve having a sewing ringto which the coupling stent attaches.

The contracted state of the coupling stent in the delivery system may beconical, tapering down in a distal direction. Furthermore, the ballooncatheter further may include a generally conical nose cone on a distalend thereof that extends through the heart valve and engages a distalend of the coupling stent in its contracted state. Desirably, the handlecomprises a proximal section and a distal section that may be coupledtogether in series to form a continuous lumen, wherein the distalsection is adapted to couple to the hub of the holder to enable manualmanipulation of the heart valve using the distal section prior toconnection with the proximal handle section. In one embodiment, theballoon catheter and proximal handle section are packaged together withthe balloon within the proximal section lumen. Alternatively, the heartvalve mounted on the holder is packaged separately from the handle andthe balloon catheter.

A further understanding of the nature and advantages of the presentinvention are set forth in the following description and claims,particularly when considered in conjunction with the accompanyingdrawings in which like parts bear like reference numerals.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be explained and other advantages and featureswill appear with reference to the accompanying schematic drawingswherein:

FIG. 1 is an anatomic anterior view of a human heart, with portionsbroken away and in section to view the interior heart chambers andadjacent structures;

FIG. 2 is an anatomic superior view of a section of the human heartshowing the tricuspid valve in the right atrium, the mitral valve in theleft atrium, and the aortic valve in between, with the tricuspid andmitral valves open and the aortic and pulmonary valves closed duringventricular diastole (ventricular filling) of the cardiac cycle;

FIG. 3 is an anatomic superior view of a section of the human heartshown in FIG. 2, with the tricuspid and mitral valves closed and theaortic and pulmonary valves opened during ventricular systole(ventricular emptying) of the cardiac cycle;

FIG. 4 is an anatomic anterior perspective view of the left and rightatria, with portions broken away and in section to show the interior ofthe heart chambers and associated structures, such as the fossa ovalis,coronary sinus, and the great cardiac vein;

FIGS. 5A-5E are sectional views through an isolated aortic annulusshowing a portion of the adjacent left ventricle below the ascendingaorta, and illustrating a number of steps in sutureless deployment of anexemplary unitary prosthetic heart valve disclosed herein, namely:

FIG. 5A shows a unitary prosthetic heart valve mounted on a ballooncatheter advancing into position within the aortic annulus;

FIG. 5B shows the unitary prosthetic heart valve in a desired implantposition at the aortic annulus, with the balloon catheter advancedfarther to displace a nose cone out of engagement with a coupling stent;

FIG. 5C shows the balloon on the catheter inflated to expand and deploythe flared coupling stent against and below the aortic annulus;

FIG. 5D shows the deflated balloon on the catheter along with the nosecone being removed from within the heart valve; and

FIG. 5E shows the fully implanted unitary prosthetic heart valve;

FIG. 6 is an exploded view of an exemplary system for delivering theunitary prosthetic heart valve;

FIG. 7 is an assembled view of the delivery system of FIG. 6 showing anose cone extending over a distal end of a valve coupling stent;

FIG. 8 is a view like FIG. 7 but with a balloon catheter displaceddistally to disengage the nose cone from the coupling stent;

FIGS. 9A and 9B are perspective views of an exemplary unitary prostheticheart valve assembled on a valve holder;

FIG. 9C is a side elevational view of the assembly of FIGS. 9A and 9B;

FIGS. 9D and 9E are distal and proximal plan views of the assembly ofFIGS. 9A and 9B;

FIGS. 10A and 10B illustrate an exemplary coupling stent shown,respectively, in both a flat and a tubular expanded configuration;

FIGS. 11A-11B illustrate an alternative coupling stent having adiscontinuous upper end in both flat and tubular expandedconfigurations;

FIG. 12A-12D are plan views of still further alternative couplingstents;

FIGS. 13A-13K are perspective cutaway views of an aortic annulus showinga portion of the adjacent left ventricle below the ascending aorta, andillustrating a number of steps in deployment of an alternative unitaryprosthetic heart valve disclosed herein, namely:

FIG. 13A shows the heart valve after removal from a storage and shippingjar and during attachment of an internally threaded leaflet partingsleeve to a heart valve holder;

FIG. 13B shows a preliminary step in preparing an aortic annulus forreceiving the heart valve including installation of guide sutures;

FIG. 13C shows the heart valve mounted on distal section of a deliveryhandle advancing into position within the aortic annulus along the guidesutures;

FIG. 13D shows the heart valve in a desired implant position at theaortic annulus, and during placement of suture snares;

FIG. 13E shows forceps bending upper ends of the suture snares outwardto improve access to the heart valve and implant site;

FIG. 13F shows a balloon catheter descending toward the implant siteprior to insertion through the delivery handle, holder and heart valve;

FIG. 13G shows the delivery handle proximal and distal sections matedand the distal end of the balloon catheter below a coupling stent of theheart valve prior to inflation of the balloon;

FIG. 13H shows the balloon of the balloon catheter inflation to expandthe coupling stent;

FIG. 13I shows the balloon deflated;

FIG. 13J shows three fastener clips descending down the guide suturesafter removal of the snares;

FIG. 13K shows the fully implanted unitary prosthetic heart valve withthe fastener clips secured on the proximal face of a sewing ring duringremoval of the guide sutures;

FIGS. 14 and 15 are upper and lower perspective views of the alternativeunitary prosthetic heart valve assembled on the valve holder;

FIG. 16 is a lower perspective view of the valve holder of FIG. 14;

FIGS. 17A-17F are a number of plan and elevational views of thealternative unitary prosthetic heart valve and holder assembly of FIGS.14 and 15;

FIGS. 18A-18C are elevational and top and bottom plan views of thecoupling stent of the heart valve of FIGS. 14-17 with a second end in acontracted state and forming a conical shape;

FIGS. 19A-19D are elevational, top and bottom plan, and perspectiveviews of the coupling stent of the heart valve of FIGS. 14-17 with thesecond end in an expanded state and also forming a conical shape;

FIGS. 20A-20C are perspective, elevational and longitudinal sectionalviews of a system for delivering the heart valve of FIGS. 14-17 showinga balloon on a balloon catheter in an inflated configuration andomitting the coupling stent of the heart valve;

FIG. 21 is an elevational view of the delivery system of FIGS. 20A-20Cwith the coupling stent of the heart valve;

FIG. 22 is an exploded view of several components of the delivery systemof FIG. 21, without the balloon catheter, heart valve and holder;

FIG. 23 is an exploded perspective view of the delivery system of FIGS.20A-20C, heart valve and holder; and

FIGS. 24A-24D are perspective, elevational and longitudinal sectionalviews of the balloon catheter and proximal handle section of thedelivery system of FIGS. 20A-20C.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention attempts to overcome drawbacks associated withconventional, open-heart surgery, while also adopting some of thetechniques of newer technologies which decrease the duration of thetreatment procedure. The prosthetic heart valves of the presentinvention are primarily intended to be delivered and implanted usingconventional surgical techniques, including the aforementionedopen-heart surgery. There are a number of approaches in such surgeries,all of which result in the formation of a direct access pathway to theparticular heart valve annulus. For clarification, a direct accesspathway is one that permits direct (i.e., naked eye) visualization ofthe heart valve annulus. In addition, it will be recognized thatembodiments of the unitary prosthetic heart valves described herein mayalso be configured for delivery using percutaneous approaches, and thoseminimally-invasive surgical approaches that require remote implantationof the valve using indirect visualization.

One primary aspect of the present invention is a unitary prostheticheart valve including implanting a tissue anchor at the same time as avalve member resulting in certain advantages. The exemplary unitaryprosthetic heart valve of the present invention has a hybrid valvemember with non-expandable and expandable portions. By utilizing anexpandable stent coupled to a non-expandable valve member, the durationof the anchoring operation is greatly reduced as compared with aconventional sewing procedure utilizing an array of sutures. Theexpandable stent may simply be radially expanded outward into contactwith the implantation site, or may be provided with additional anchoringmeans, such as barbs. The operation may be carried out using aconventional open-heart approach and cardiopulmonary bypass. In oneadvantageous feature, the time on bypass is greatly reduced due to therelative speed of implanting the expandable stent.

For definitional purposes, the terms “stent” or “coupling stent” referto a structural component of a heart valve that is capable of attachingto tissue of a heart valve annulus. The coupling stents described hereinare most typically tubular stents, or stents having varying shapes ordiameters. A stent is normally formed of a biocompatible metal frame,such as stainless steel or Nitinol. More preferably, in the context ofthe present invention the stents are made from laser-cut tubing of aplastically-expandable metal. Other coupling stents that could be usedwith valves of the present invention include rigid rings, spirally-woundtubes, and other such tubes that fit tightly within a valve annulus anddefine an orifice therethrough for the passage of blood. It is entirelyconceivable, however, that the coupling stent could be separate clampsor hooks that do not define a continuous periphery. Although suchdevices sacrifice some contact uniformity, and speed and ease ofdeployment, these devices could be configured to work in conjunctionwith a particular valve member.

A distinction between self-expanding and balloon-expanding stents existsin the field. A self-expanding stent may be crimped or otherwisecompressed into a small tube and possesses sufficient elasticity tospring outward by itself when a restraint such as an outer sheath isremoved. In contrast, a balloon-expanding stent is made of a materialthat is substantially less elastic, and indeed must be plasticallyexpanded from the inside out when converting from a contracted to anexpanded diameter. It should be understood that the termballoon-expanding stents encompasses plastically-expandable stents,whether or not a balloon is used to actually expand it (e.g., a devicewith mechanical fingers could expand the stent). The material of thestent plastically deforms after application of a deformation force suchas an inflating balloon or expanding mechanical fingers. Consequently,the term “balloon-expandable stent” should be considered to refer to thematerial or type of the stent as opposed to the specific expansionmeans.

The term “valve member” refers to that component of a heart valve thatpossesses the fluid occluding surfaces to prevent blood flow in onedirection while permitting it in another. As mentioned above, variousconstructions of valve members are available, including those withflexible leaflets and those with rigid leaflets, or even a ball and cagearrangement. The leaflets may be bioprosthetic, synthetic, metallic, orother suitable expedients.

A primary focus of the present invention is a unitary prosthetic heartvalve having a single stage implantation in which a surgeon secures ahybrid coupling stent and valve member to a valve annulus as one unit orpart. Certain features of the hybrid coupling stent and valve member aredescribed in co-pending U.S. Provisional Application No. 61/139,398,filed Dec. 19, 2008, the contents of which are expressly incorporatedherein. It should be noted that “two-stage” prosthetic valve deliverydisclosed in the aforementioned application refers to the two primarysteps of a) anchoring structure to the annulus, and then b) connecting avalve member, which does not necessarily limit the valve to just twoparts. Likewise, the unitary valve described herein is especiallybeneficial in a single stage implant procedure, but that does notnecessarily limit the overall system to just one part. For instance, theheart valve 30 disclosed herein could also use an expanding base stentwhich is then reinforced by the subsequently implanted heart valve.Because the heart valve 30 has a non-expandable and non-collapsibleannular support structure, and a plastically-expandable coupling stent36, it effectively resists recoil of a self-expanded base stent. Thatsaid, various claims appended hereto may exclude more than one part.

As a point of further definition, the term “expandable” is used hereinto refer to a component of the heart valve capable of expanding from afirst, delivery diameter to a second, implantation diameter. Anexpandable structure, therefore, does not mean one that might undergoslight expansion from a rise in temperature, or other such incidentalcause such as fluid dynamics acting on leaflets or commissures.Conversely, “non-expandable” should not be interpreted to meancompletely rigid or a dimensionally stable, as some slight expansion ofconventional “non-expandable” heart valves, for example, may beobserved.

In the description that follows, the term “body channel” is used todefine a blood conduit or vessel within the body. Of course, theparticular application of the prosthetic heart valve determines the bodychannel at issue. An aortic valve replacement, for example, would beimplanted in, or adjacent to, the aortic annulus. Likewise, a mitralvalve replacement will be implanted at the mitral annulus. Certainfeatures of the present invention are particularly advantageous for oneimplantation site or the other, in particular the aortic annulus.However, unless the combination is structurally impossible, or excludedby claim language, any of the heart valve embodiments described hereincould be implanted in any body channel.

A “quick-connect” aortic valve bio-prosthesis described herein is asurgically-implanted medical device for the treatment of aortic valvestenosis. The exemplary quick-connect device comprises an implantablebio-prosthesis and a delivery system for its deployment. The device,delivery system and method of use take advantage of the provenhemodynamic performance and durability of existing commerciallyavailable, non-expandable prosthetic heart valves, such as theCarpentier-Edwards PERIMOUNT Magna® Aortic Heart Valve available fromEdwards Lifesciences of Irvine, Calif., while improving its ease of useand reducing total procedure time. This is mainly accomplished byeliminating the need to suture the bio-prosthesis onto the nativeannulus as is currently done per standard surgical practice, andtypically requires 12-24 manually tied sutures around the valveperimeter. Also, the technique may obviate the need to excise theleaflets of the calcified valve and debride or smooth the valve annulus.

FIGS. 5A-5E are sectional views through an isolated aortic annulus AAshowing a portion of the adjacent left ventricle LV and ascending aortawith sinus cavities S. The two coronary sinuses CS are also shown. Theseries of views show snapshots of a number of steps in deployment of anexemplary prosthetic heart valve system of the present invention, whichcomprises a unitary system. A coupling stent of a unitary prostheticvalve is deployed against the native leaflets or, if the leaflets areexcised, against the debrided aortic annulus AA.

FIG. 5A shows a unitary heart valve 30 mounted on a balloon catheter 32having a balloon 40 (FIG. 5B) in a deflated state near a distal end andadvancing into position so that it is approximately axially centered atthe aortic annulus AA. The unitary heart valve 30 comprises a prostheticvalve 34 and a coupling stent 36 attached to and projecting from adistal end thereof. In its radially constricted or undeployed state, thecoupling stent 36 assumes a conical inward taper in the distaldirection. The catheter 32 extends through the heart valve 30 andterminates in a distal nose cone 38 which has a conical or bell-shapeand covers the tapered distal end of the coupling stent 36. As will beshown below, the catheter 32 extends through an introducing cannula andvalve holder.

When used for aortic valve replacement, the prosthetic valve 34preferably has three flexible leaflets which provide the fluid occludingsurfaces to replace the function of the native valve leaflets. Invarious preferred embodiments, the valve leaflets may be taken fromanother human heart (cadaver), a cow (bovine), a pig (porcine valve) ora horse (equine). In other preferred variations, the valve member maycomprise mechanical components rather than biological tissue. The threeleaflets are supported by a non-expandable, non-collapsible annularsupport structure and a plurality of commissure posts projecting in anoutflow direction. Typical prosthetic heart valves with flexibleleaflets include a synthetic (metallic and/or polymeric) supportstructure of one or more components covered with cloth for ease ofattachment of the leaflets.

For instance, in a preferred embodiment, the prosthetic valve 34comprises a commercially available, non-expandable prosthetic heartvalve, such as the Carpentier-Edwards PERIMOUNT Magna® Aortic HeartValve available from Edwards Lifesciences. In this sense, a“commercially available” prosthetic heart valve is an off-the-shelf(i.e., suitable for stand-alone sale and use) prosthetic heart valvedefining therein a non-expandable, non-collapsible support structure andhaving a sewing ring capable of being implanted using sutures throughthe sewing ring in an open-heart, surgical procedure. The particularapproach into the heart used may differ, but in surgical procedures theheart is stopped and opened, in contrast to beating heart procedureswhere the heart remains functional. To reiterate, the terms“non-expandable” and “non-collapsible” should not be interpreted to meancompletely rigid and dimensionally stable, merely that the valve is notexpandable/collapsible like some proposed minimally-invasively orpercutaneously-delivered valves.

The prosthetic valve 34 is provided with an expandable couplingmechanism in the form of the coupling stent 36 for securing the valve tothe annulus. Although the coupling stent 36 is shown, the couplingmechanism may take a variety of different forms, but eliminates the needfor connecting sutures and provides a rapid connection means as it doesnot require the time-consuming process of suturing it to the annulus.

An implant procedure involves delivering the heart valve 30 andexpanding the coupling stent 36 at the aortic annulus. Because the valve34 is non-expandable, the entire procedure is typically done using theconventional open-heart technique. However, because the coupling stent36 is implanted by simple expansion, with reduced suturing, the entireoperation takes less time. This hybrid approach will also be much morecomfortable to surgeons familiar with the open-heart procedures andcommercially available heart valves.

Moreover, the relatively small change in procedure coupled with the useof proven heart valves should create a much easier regulatory path thanstrictly expandable, remote procedures. Even if the system must bevalidated through clinical testing to satisfy the Pre-Market Approval(PMA) process with the FDA (as opposed to a 510k submission), at leastthe surgeon acceptance of the quick-connect heart valve 30 will begreatly streamlined with a commercial heart valve that is alreadyproven, such as the Magna® Aortic Heart Valve.

In FIG. 5B the heart valve 30 has advanced to a desired implant positionat the aortic annulus AA. The prosthetic valve 34 may include asuture-permeable ring 42 that desirably abuts the aortic annulus AA.More preferably, the sewing ring 42 is positioned supra-annularly, orabove the narrowest point of the aortic annulus AA, so as to allowselection of a larger orifice size than a valve placed intra-annularly.Furthermore, with annulus expansion using the coupling stent 36, and thesupra-annular placement, the surgeon may select a valve having a sizeone or two increments larger than previously conceivable. As mentioned,the prosthetic valve 34 is desirably a commercially available heartvalve having a sewing ring 42. The balloon catheter 32 has advancedrelative to the heart valve 30 to displace the nose cone 38 out ofengagement with the coupling stent 36. A dilatation balloon 40 on thecatheter 32 can be seen just beyond the distal end of the coupling stent36.

FIG. 5C shows the balloon 40 on the catheter 32 inflated to expand anddeploy the coupling stent 36 against the annulus. The balloon 40 isdesirably inflated using controlled, pressurized, sterile physiologicsaline. The coupling stent 36 transitions between its conical contractedstate and its generally tubular or slightly conical expanded state.Simple interference between the coupling stent 36 and the annulus may besufficient to anchor the heart valve 30, or interacting features such asprojections, hooks, barbs, fabric, etc. may be utilized.

In a preferred embodiment, the coupling stent 36 comprises aplastically-expandable cloth-covered stainless-steel tubular stent. Oneadvantage of using a plastically-expandable stent is the ability toexpand the native annulus to receive a larger valve size than wouldotherwise be possible with conventional surgery. Desirably, the leftventricular outflow tract (LVOT) is significantly expanded by at least10%, or for example by 1.0-5 mm, and the surgeon can select a heartvalve 30 with a larger orifice diameter relative to an unexpandedannulus. Even a 1 mm increase in annulus size is significant since thegradient is considered to be proportional to the radius raised to the4^(th) power.

The stent body is preferably configured with sufficient radial strengthfor pushing aside the native leaflets and holding the native leafletsopen in a dilated condition. The native leaflets provide a stable basefor holding the stent, thereby helping to securely anchor the stent inthe body. To further secure the stent to the surrounding tissue, thelower portion may be configured with anchoring members, such as, forexample, hooks or barbs (not shown). It should be understood that thecoupling stent 36 is desirably robust enough to anchor the heart valve30 directly against the native annulus (with or without leafletexcision) in the absence of a pre-deployed base stent.

Also, the balloon 40 may have a larger distal expanded end than itsproximal expanded end so as to apply more force to the free end of thecoupling stent 36 than to the prosthetic valve 34. In this way, theprosthetic valve 34 and flexible leaflets therein are not subject tohigh expansion forces from the balloon 40. Indeed, although balloondeployment is shown, the coupling stent 36 may also be a self-expandingtype of stent. In the latter configuration, the nose cone 38 is adaptedto retain the coupling stent 36 in its constricted state prior toposition in the heart valve 30 within the aortic annulus.

As noted above, the coupling stent 36 described herein can be a varietyof designs, including having the diamond/chevron-shaped openings shownor other configurations. Further, the coupling stent 36 may includebarbs or other tissue anchors to further secure the stent to the tissue.The barbs could be deployable (e.g., configured to extend or be pushedradially outward) by the expansion of a balloon. Alternatively, shapememory material may be utilized such that the barbs bend or curl uponimplant. The material of the coupling stent 36 depends on the mode ofdelivery (i.e., balloon- or self-expanding), and the stent can be barestrut material or covered to promote ingrowth and/or to reduceparavalvular leakage. Preferably, the coupling stent 36 is covered topromote in-growth and/or to reduce paravalvular leakage, such as with aDacron tube or the like.

FIG. 5D shows the deflated balloon 40 on the catheter 32 along with thenose cone 38 being removed from within the heart valve 30. Finally, FIG.5E shows the fully deployed prosthetic heart valve system of the presentinvention including the heart valve 30 coupled to the aortic annulus AA.

FIG. 6 is an exploded view, and FIGS. 7 and 8 are assembled views, of anexemplary system 50 for delivering the prosthetic heart valve of thepresent invention. The delivery system 50 includes a balloon catheter 52having the balloon 40 on its distal end and an obturator 54 on aproximal end. The obturator 54 presents a proximal coupling 56 thatreceives a luer connector or other such fastener of a Y-fitting 58.

The aforementioned nose cone 38 may attach to the distalmost end of thecatheter 52, but more preferably attaches to a wire (not shown) insertedthrough the center lumen of the balloon catheter 52. The nose cone 38preferably secures to the end of a 0.035″ guide wire and has a taperedgeometry that fits onto the tapered geometry of the tapered couplingstent 36 to protect it and prevent accidental calcium dislodgementcaused by the stent catching as it advances into the native calcifiedaortic valve. The nose cone 38 assembles onto the distal end of theheart valve 30 prior to positioning the device into the aortic root fordeployment. The nose cone 38 is assembled by distally loading the guidewire into the thru lumen of the balloon catheter 52 and advancingproximally until the it sits and conforms to the tapered coupling stent36. Once the prosthesis is in the desired location and prior to balloonexpansion, the surgeon advances the nose cone 38 in the ventriculardirection to allow balloon expansion. As it advances in the ventriculardirection and disengages the stent frame, the nose cone 38 collapses toa size that allows retrieval through the deployed aortic valve.

The catheter 52 and the nose cone 38 pass through a hollow handle 60having a proximal section 62 and a distal section 64. A distal end ofthe distal handle section 64 firmly attaches to a hub 66 of a valveholder 68, which in turn attaches to the prosthetic heart valve 30.Details of the valve holder 68 will be given below with reference toFIGS. 9A-9E.

The two sections 62, 64 of the handle 60 are desirably formed of a rigidmaterial, such as a molded plastic, and coupled to one another to form arelatively rigid and elongated tube for manipulating the prostheticheart valve 30 attached to its distal end. In particular, the distalsection 64 may be easily coupled to the holder hub 66 and thereforeprovide a convenient tool for managing the heart valve 30 duringpre-surgical rinsing steps. For this purpose, the distal section 64features a distal tubular segment 70 that couples to the holder hub 66,and an enlarged proximal segment 72 having an opening on its proximalend that receives a tubular extension 74 of the proximal handle section62.

FIG. 6 shows an O-ring 76 that may be provided on the exterior of thetubular extension 74 for a frictional interference fit to prevent thetwo sections from disengaging. Although not shown, the distal tubularsegment 70 may also have an O-ring for firmly coupling to the holder hub66, or may be attached with threading or the like. In one preferredembodiment, the balloon 40 on the catheter 52 is packaged within theproximal handle section 62 for protection and ease of handling. Couplingthe proximal and distal handle sections 62, 64 therefore “loads” thesystem 50 such that the balloon catheter 52 may be advanced through thecontinuous lumen leading to the heart valve 30.

In a preferred embodiment, the prosthetic heart valve 30 incorporatesbioprosthetic tissue leaflets and is packaged and stored attached to theholder 68 but separate from the other introduction system 50 components.Typically, bioprosthetic tissue is packaged and stored in a jar withpreservative solution for long shelf life, while the other componentsare packaged and stored dry.

When assembled as seen in FIGS. 7 and 8, an elongated lumen (notnumbered) extends from the proximal end of the Y-fitting 58 to theinterior of the balloon 40. The Y-fitting 58 desirably includes aninternally threaded connector 80 for attachment to an insufflationsystem, or a side port 82 having a luer fitting 84 or similar expedientmay be used for insufflation of the balloon 40.

FIGS. 7 and 8 show two longitudinal positions of the catheter 52 andassociated structures relative to the handle 60 and its associatedstructures. In a retracted position shown in FIG. 7, the balloon 40primarily resides within the distal handle section 64. FIG. 7illustrates the delivery configuration of the introduction system 50, inwhich the surgeon advances the prosthetic heart valve 30 from outsidethe body into a location adjacent the target annulus. The nose cone 38extends around and protects a distal end of the conical undeployedcoupling stent 36. This configuration is also seen in FIG. 5A, albeitwith the holder 68 removed for clarity. Note the spacing S between theproximal coupling 56 and the proximal end of the handle 60.

As explained above with respect to FIGS. 5A-5E, the surgeon advances theprosthetic heart valve 30 into its desired implantation position at thevalve annulus, and then advances the balloon 40 through the heart valveand inflates it. To do so, the operator converts the delivery system 50from the retracted configuration of FIG. 7 to the deploymentconfiguration of FIG. 8, with the balloon catheter 40 displaced distallyas indicated by the arrow 78 to disengage the nose cone 38 from thecoupling stent 36. Note that the proximal coupling 56 now contacts theproximal end of the handle 60, eliminating the space S indicated in FIG.7.

Prior to a further description of operation of the delivery system 50, amore detailed explanation of the heart valve 30 and valve holder 68 isnecessary. FIGS. 9A-9E show a number of perspective and other views ofthe exemplary heart valve 30 mounted on the delivery holder 68 of thepresent invention. As mentioned, the heart valve 30 comprises theprosthetic valve 34 having the coupling stent 36 attached to an inflowend thereof. In a preferred embodiment, the prosthetic valve 34comprises a commercially available off-the-shelf non-expandable,non-collapsible commercial prosthetic valve. Any number of prostheticheart valves can be retrofit to attach the coupling stent 36, and thusbe suitable for use in the context of the present invention. Forexample, the prosthetic valve 34 may be a mechanical valve or a valvewith flexible leaflets, either synthetic or bioprosthetic. In apreferred embodiment, however, the prosthetic valve 34 includesbioprosthetic tissue leaflets 86 (FIG. 9A). Furthermore, as mentionedabove, the prosthetic valve 34 is desirably a Carpentier-EdwardsPERIMOUNT Magna® Aortic Heart Valve (e.g., model 3000TFX) available fromEdwards Lifesciences of Irvine, Calif.

The coupling stent 36 preferably attaches to the ventricular (or inflow)aspect of the valve's sewing ring 42 during the manufacturing process ina way that preserves the integrity of the sewing ring and preventsreduction of the valve's effective orifice area (EOA). Desirably, thecoupling stent 36 will be continuously sutured to the sewing ring 42 ina manner that maintains the outer contours of the sewing ring. Suturesmay be passed through apertures or eyelets in the stent skeleton, orthrough a cloth covering that in turn is sewn to the skeleton. Otherconnection solutions include prongs or hooks extending inward from thestent, ties, Velcro, snaps, adhesives, etc. Alternatively, the couplingstent 36 may be more rigidly connected to rigid components within theprosthetic valve 34. During implant, therefore, the surgeon can seat thesewing ring 42 against the annulus in accordance with a conventionalsurgery. This gives the surgeon familiar tactile feedback to ensure thatthe proper patient-prosthesis match has been achieved. Moreover,placement of the sewing ring 42 against the outflow side of the annulushelps reduce the probability of migration of the heart valve 30 towardthe ventricle.

The coupling stent 36 may be a pre-crimped, tapered, 316L stainlesssteel balloon-expandable stent, desirably covered by a polyester skirt88 to help seal against paravalvular leakage and promote tissue ingrowthonce implanted within the annulus (see FIG. 5E). The coupling stent 36transitions between the tapered constricted shape of FIGS. 5A-5B and9A-9E to its flared expanded shape shown in FIGS. 5C-5E.

The coupling stent 36 desirably comprises a plurality of sawtooth-shapedor otherwise angled, serpentine or web-like struts 90 connected to threegenerally axially-extending posts 92. As will be seen below, the posts92 desirably feature a series of evenly spaced apertures to whichsutures holding the polyester skirt 88 in place may be anchored. As seenbest in FIG. 5E, the stent 36 when expanded flares outward and conformsclosely against the inner surface of the annulus, and has an axiallength as great as or greater than that of the prosthetic valve 34.Anchoring devices such as barbs or other protruberances from thecoupling stent 36 may be provided to enhance the frictional hold betweenthe coupling stent and the annulus.

It should be understood that the particular configuration of thecoupling stent, whether possessing straight or curvilinear struts 90,may be modified as needed. There are numerous stent designs, asdescribed below with reference to FIGS. 10-12D, any of which potentiallymay be suitable. Likewise, although the preferred embodimentincorporates a balloon-expandable coupling stent 36, a self-expandingstent could be substituted with certain modifications, primarily to thedelivery system. In a preferred embodiment, the coupling stent 36 isdesirably plastically-expandable to provide a firmer anchor for thevalve 34 to the annulus with or without native leaflets. The stent maybe expanded using a balloon or mechanical expander as described below.

Still with reference to FIGS. 9A-9E, the holder 68 comprises theaforementioned proximal hub 66 and a thinner distal extension 94 thereofforming a central portion of the holder. Three legs 96 a, 96 b, 96 ccircumferentially equidistantly spaced around the central extension 94and projecting radially outward therefrom comprise inner struts 98 andouter commissure rests 100. The prosthetic valve 34 preferably includesa plurality, typically three, commissures 102 that project in an outflowdirection. Although not shown, the commissure rests 100 preferablyincorporate depressions into which the tips of the commissures 102 canfit.

In one embodiment, the holder 68 is formed of a rigid polymer such asDelrin or polypropylene that is transparent to increase visibility of animplant procedure. As best seen in FIG. 9E, the holder 68 exhibitsopenings between the legs 96 a, 96 b, 96 c to provide a surgeon goodvisibility of the valve leaflets 86, and the transparency of the legsfurther facilitates visibility and permits transmission of lighttherethrough to minimize shadows. Although not described in detailherein, FIG. 9E also illustrate a series of through holes in the legs 96a, 96 b, 96 c permitting connecting sutures to be passed through fabricin the prosthetic valve 34 and across a cutting guide in each leg. As isknown in the art, severing a middle length of suture that is connectedto the holder 68 and passes through the valve permits the holder to bepulled free from the valve when desired.

FIGS. 9C and 9D illustrate a somewhat modified coupling stent 36 fromthat shown in FIGS. 9A and 9B, wherein the struts 90 andaxially-extending posts 92 are better defined. Specifically, the posts92 are somewhat wider and more robust than the struts 90, as the latterprovide the stent 36 with the ability to expand from the conical shapeshown to a more tubular configuration. Also, a generally circularreinforcing ring 104 abuts the valve sewing ring 42. Both the posts 92and the ring 104 further include a series of through holes 106 that maybe used to secure the polyester skirt 88 to the stent 36 using suturesor the like. A number of variants of the coupling stent 36 are alsodescribed below.

FIGS. 10A-10B illustrate the exemplary coupling stent 36 in both flatand tubular configurations, the latter which is generally the expandedshape. As mentioned, the web-like struts 90 and a reinforcing ring 104connect three generally axially-extending posts 92. A plurality ofevenly spaced apertures 106 provide anchors for holding the polyesterskirt 88 (see FIG. 9B) in place. In the illustrated embodiment, theweb-like struts 90 also include a series of axially-extending struts108. An upper end of the coupling stent 36 that connects to the sewingring of the valve and is defined by the reinforcing ring 104 follows anundulating path with alternating arcuate troughs 110 and peaks 112. Asseen from FIG. 9C, the exemplary prosthetic valve 34 has an undulatingsewing ring 42 to which the upper end of the coupling stent 36 conforms.In a preferred embodiment, the geometry of the stent 36 matches that ofthe undulating sewing ring 42. Of course, if the sewing ring of theprosthetic valve is planar, then the upper end of the coupling stent 36will also be planar. It should be noted also that the tubular version ofFIG. 10B is an illustration of an expanded configuration, although theballoon 40 may over-expand the free (lower) end of the stent 36 suchthat it ends up being slightly conical.

FIGS. 11A and 11B show an alternative coupling stent 120, again inflattened and tubular configurations, respectively. As with the firstembodiment, the coupling stent 120 includes web-like struts 122extending between a series of axially-extending struts 124. In thisembodiment, all of the axially-extending struts 124 are substantiallythe same thin cross-sectional size. The upper or connected end of thestent 120 again includes a reinforcing ring 126, although this versionis interrupted with a series of short lengths separated by gaps. Theupper end defines a plurality of alternating troughs 128 and peaks 130,with lengths of the reinforcing ring 126 defining the peaks. Theaxially-extending struts 124 are in-phase with the scalloped shape ofthe upper end of the stent 120, and coincide with the peaks and themiddle of the troughs.

The gaps between the lengths making up the reinforcing ring 126 permitthe stent 120 to be matched with a number of different sized prostheticvalves 34. That is, the majority of the stent 120 is expandable having avariable diameter, and providing gaps in the reinforcing ring 126 allowsthe upper end to also have a variable diameter so that it can be shapedto match the size of the corresponding sewing ring. This reducesmanufacturing costs as correspondingly sized stents need not be used foreach different sized valve.

FIG. 12A is a plan view of a still further alternative coupling stent132 that is very similar to the coupling stent 120, including web-likestruts 134 connected between a series of axially-extending struts 136,and the upper end is defined by a reinforcing ring 138 formed by aseries of short lengths of struts. In contrast to the embodiment ofFIGS. 11A and 11B, the peaks of the undulating upper end have gaps asopposed to struts. Another way to express this is that theaxially-extending struts 136 are out-of-phase with the scalloped shapeof the upper end of the stent 132, and do not correspond to the peaksand the middle of the troughs.

FIG. 12B illustrates an exemplary coupling stent 140 again having theexpandable struts 142 between the axially-extending struts 144, and anupper reinforcing ring 146. The axially-extending struts 144 arein-phase with peaks and troughs of the upper end of the stent. Thereinforcing ring 146 is a cross between the earlier-described such ringsas it is continuous around its periphery but also has a variablethickness or wire diameter. That is, the ring 146 comprises a series oflengths of struts 148 of fixed length connected by thinner bridgeportions 150 of variable length, or in other words which are extendible.The bridge portions 150 are each formed with a radius so that they canbe either straightened (lengthened) or bent more (compressed). A seriesof apertures 152 are also formed in an upper end of the stent 142provide anchor points for sutures or other attachment means whensecuring the stent to the sewing ring of the corresponding prostheticvalve.

In FIG. 12C, an alternative coupling stent 154 is identical to the stent140 of FIG. 12B, although the axially-extending struts 156 areout-of-phase with the peaks and troughs of the undulating upper end.

FIG. 12D shows a still further variation on a coupling stent 160, whichhas a series of expandable web-like struts 162 in sawtooth patternsconnecting axially-extending struts 164. As with the version shown inFIGS. 10A and 10B, the web-like struts 162 are also connected by aseries of axially-extending struts 166, although these are thinner thanthe main axial struts 164. A reinforcing ring 168 is also thicker thanthe web-like struts 162, and features one or more gaps 170 in eachtrough such that the ring is discontinuous and expandable. Barbs 172,174 on the axially extending struts 164, 166 may be utilized to enhanceretention between the coupling stent 160 and annular tissue within whichit seats.

As an alternative to a balloon, a mechanical expander (not shown) may beused to expand the coupling stent 36 shown above. For instance, amechanical expander may include a plurality of spreadable fingersactuated by a syringe-like apparatus, as seen in U.S. ProvisionalApplication No. 61/139,398, incorporated above. The fingers are axiallyfixed but capable of pivoting or flexing with respect to a barrel. Thedistal end of a plunger has an outer diameter that is greater than thediameter circumscribed by the inner surfaces of the spreadable fingers,such that distal movement of the plunger with respect to the barrelgradually cams the fingers outward within the coupling stent. Therefore,the term “plastically-expandable” encompasses materials that can besubstantially deformed by an applied force to assume a different shape.Some self-expanding stents may be deformed to a degree by an appliedforce beyond their maximum expanded dimension, but the primary cause ofthe shape change is elastic rebound as opposed to a plastic deformation.

The unitary heart valve 30 described above may be mounted on a ballooncatheter advanced into implant position thereon, or the balloon cathetermay be introduced after the valve has been delivered to the annulus.FIGS. 13A-13K illustrate an implant sequence wherein a surgeon firstdelivers an alternative unitary heart valve 200 to an aortic annulus andthen introduces a balloon catheter to deploy a coupling stent 202. Itshould be understood that the same procedure may be carried out usingthe aforementioned heart valve 30, as well as any combination of valveand coupling stent disclosed herein.

FIG. 13A shows the unitary heart valve 200 after removal from a storageand shipping jar and during attachment of an internally threaded leafletparting sleeve 204 to a heart valve holder 206. The heart valve 200 issimilar to the heart valve 30 described above in that it comprises aprosthetic valve 208 and the coupling stent 202 attached to andprojecting from an inflow end thereof. The prosthetic valve 208desirably has three flexible leaflets 210 supported by a non-expandable,non-collapsible annular support structure 212 and a plurality ofcommissure posts 214 projecting in an outflow direction. Asuture-permeable ring 216 circumscribes an inflow end of the prostheticvalve 208. As mentioned above, the prosthetic valve 208 comprises asynthetic (metallic and/or polymeric) support structure of one or morecomponents covered with cloth for ease of attachment of the leaflets. Inone exemplary form, the prosthetic valve 208 is a commerciallyavailable, non-expandable prosthetic heart valve, such as theCarpentier-Edwards PERIMOUNT Magna® Aortic Heart Valve available fromEdwards Lifesciences. Further details of the unitary heart valve 200will be described below with reference to FIGS. 14-19.

In FIG. 13A and in the ensuing procedure drawings, the unitary heartvalve 200 is oriented with an inflow end down and an outflow end up.Therefore, the terms inflow and down may be used interchangeably attimes, as well as the terms outflow and up. Furthermore, the termsproximal and distal are defined from the perspective of the surgeondelivering the valve inflow end first, and thus proximal is synonymouswith up or outflow, and distal with down or inflow.

The leaflet parting sleeve 204 mounts to one end of an assembly tube220. Although not shown, the sleeve 204 preferably fits snugly over theend of the tube 220 with a slight interference, so that it may bedecoupled therefrom with ease. Some form of minimal latch may also beprovided. The coupling stent 202 has a first end (not shown) connectedto the inflow end of the prosthetic valve 208 and a lower second end 222that is shown in a contracted state for delivery to an implant position.In the contracted state, the coupling stent 202 assumes a frusto-conicalshape wherein the lower second end 222 defines an opening large enoughto receive the leaflet parting sleeve 204 with clearance therebetween.The sleeve 204 includes internal threading 224 that matches externalthreading on a downwardly-directed boss 226 of the valve holder 206. Atechnician passes the sleeve 204 on the end of the tube 220 through thestent second end 222, parts the flexible leaflets 210 from the inflowside, and screws the sleeve to the boss 226. Once the technician firmlyattaches the sleeve 204, the assembly tube 220 may be easily pulled fromand removed from within the valve 200. The resulting subassembly is seenin FIG. 13C.

Attachment of the leaflet parting sleeve 204 in this manner providesseveral benefits. First and foremost, the sleeve 204 defines athroughbore at the level of the valve leaflets 210 for passage of aballoon catheter from the outflow side. Typically three valve leaflets210 span the orifice defined by the support structure 212 and have freeedges that come together or “coapt” generally along three line segmentsoriented 120° apart that intersect at the centerline. This configurationmimics a native valve and performs well in permitting blood flow in onedirection but not the other. Though extremely durable in use, the valveleaflets 210 are relatively fragile and susceptible to damage fromcontact with solid objects during the implant procedure, especially ifthey are made from bioprosthetic tissue such as bovine pericardium or aporcine xenograft. Consequently, the parting sleeve 204 opens theleaflets 210 and provides a protective barrier between them and aballoon catheter that passes through the valve, as will be seen below.Without the sleeve 204 a balloon catheter would have to force its waybackward past the coapted leaflet free edges. A further benefit of theparting sleeve 204 is the ease with which it is assembled to the holder206. Attachment through the valve 200 to the holder 206 is intuitive,and removal of the assembly sleeve 220 simple. The valve 220 and holder206 assembly are stored together prior to use, often in a storagesolution of glutaraldehyde or other preservative. The parting sleeve 204is preferably not pre-attached to the holder 206 to avoid causing anyindentations in the leaflets 210 from long-term contact therewith. Thatis, the leaflets 210 are stored in their relaxed or coapted state.

FIG. 13B shows a preliminary step in preparing an aortic annulus AA forreceiving the heart valve 200, including installation of guide sutures230. The aortic annulus AA is shown schematically isolated and it shouldbe understood that various anatomical structures are not shown forclarity. The annulus AA includes a fibrous ring of tissue that projectsinward from surrounding heart walls. The annulus AA defines an orificebetween the ascending aorta AO and the left ventricle LV. Although notshown, native leaflets projecting inward at the annulus AA to form aone-way valve at the orifice. The leaflets may be removed prior to theprocedure, or left in place as mentioned above. If the leaflets areremoved, some of the calcified annulus may also be removed, such as witha rongeur. The ascending aorta AO commences at the annulus AA with threeoutward bulges or sinuses, two of which are centered at coronary ostia(openings) CO leading to coronary arteries CA. As will be seen below, itis important to orient the prosthetic valve 208 so that the commissures214 are not aligned with and thus not blocking the coronary ostia CO.

The surgeon attaches the guide sutures 230 at three evenly spacedlocations around the aortic annulus AA. In the illustrated embodiment,the guide sutures 230 attach to locations below or corresponding to thecoronary ostia CO (that is, two guide sutures are aligned with theostia, and the third centered below the non-coronary sinus). The guidesutures 230 are shown looped twice through the annulus AA from theoutflow or ascending aorta side to the inflow or ventricular side. Ofcourse, other suturing methods or pledgets may be used depending onsurgeon preference.

FIG. 13C shows the guide sutures 230 having been secured so that eachextends in pairs of free lengths from the annulus AA and out of theoperating site. The unitary heart valve 200 mounts on a distal section240 of a delivery handle and the surgeon advances the valve intoposition within the aortic annulus AA along the guide sutures 230. Thatis, the surgeon threads the three pairs of guide sutures 230 throughevenly spaced locations around the suture-permeable ring 216. If theguide sutures 230, as illustrated, anchor to the annulus AA below theaortic sinuses, they thread through the ring 216 mid-way between thevalve commissure posts 214. The support structure 212 often includes anundulating shape of alternative commissures and cusps, and thus theguide sutures 230 pass through the suture-permeable ring 216 at thecusps of the valve. Furthermore, the exemplary ring 216 has anundulating inflow side such that the cusp locations are axially thickerthan the commissure locations, which provides more material for securingthe guide sutures 230.

Now with reference to FIG. 13D, the heart valve 200 rests in a desiredimplant position at the aortic annulus AA. The suture-permeable ring 216desirably contacts the aortic side of the annulus AA, and is thus saidto be in a supra-annular position. Such a position enables selection ofa larger orifice prosthetic valve 200 in contrast to placing the ring216, which by definition surrounds the valve orifice, within the annulusAA, or infra-annularly.

The surgeon delivers a plurality of suture snares 250 down each freelength of the guide sutures 230 into contact with the upper or outflowside of the suture-permeable ring 216. The snares 250 enable downwardpressure to be applied to the ring 216 and thus the valve 200 during theimplant procedure, which helps insure good seating of the ring 216 onthe annulus AA. The snares 250 also provide rigid enclosures around eachof the flexible guide sutures 230 which helps avoid entanglement withthe descending balloon catheter, as will be appreciated. As there arethree guide sutures 230 and six free lengths, six snares 250 areutilized, though more or less is possible. The snares 250 are typicallytubular straw-like members of medical grade plastic.

In FIG. 13E, forceps 252 are seen clamping upper ends of the suturesnares 250, and bending one pair outward to improve access to the heartvalve 200 and implant site. FIG. 13F shows all of the pairs of suturesnares 250 bent outward prior to advancement of a balloon catheter 260.Although it will be described in greater detail below, the deliverysystem includes the aforementioned handle distal section 240 formanipulating the heart valve 200 on the holder 206. The distal section240 is tubular and defines a lumen 242 for receiving the ballooncatheter 260 having a balloon 262 in an uninflated state on a distal endthereof.

Now with reference to FIG. 13G, a delivery handle proximal section 244is shown mated with the distal section 240, and the distal balloon 262is shown extending beyond the coupling stent 202 of the heart valve 200prior to inflation of the balloon.

FIGS. 13H and 13I show inflation and deflation of the balloon 262 of theballoon catheter 260, which plastically expands the coupling stent 202against the annulus AA and a portion of the left ventricle LV. As willbe explained further below, the balloon 262 expands with a conicalexterior surface so that the lower second end 222 of the stent 202expands outward wider than the first end. The resulting expanded stent202 forms a frusto-conical surface.

Subsequently, the surgeon delivers three fastener clips 270 down theguide sutures 230 after removal of the snares 250, as seen in FIG. 13J.FIG. 13K shows the fully implanted unitary prosthetic heart valve 200with the fastener clips 270 secured on the proximal face of thesuture-permeable ring 216, and shows removal of the guide sutures 230.Any number of methods are available for securing the pairs of guidesutures 230 on the outflow side of the ring 216, including conventionalknot-tying, however the fastener clips 270 are consistent with theoverall aim of shortening the implant procedure. Inclusion of the guidesutures 230 primarily insures proper rotational orientation of the valve200, as mentioned, but also helps secure the valve 200 in place at theannulus AA. That said, the guide sutures 230 may optionally be removedafter delivery of the valve 200 so that the sole means of anchoring thevalve is the expanded coupling stent 202. The latter option results in atrue “knotless” valve attachment, if not completely sutureless.

The illustrated configuration with fastener clips 270 eliminates theneed to tie suture knots, and the placement of the guide sutures 230 atthe cusps of the native valve and prosthesis separates the clips fromthe commissures, thus increasing accessibility. Even if knots are usedinstead of the clips 270, the number of knots are reduced to threebetween the commissure posts, rather than multiple knots (12-24) asbefore, some of which were behind the commissure posts. The use of threesutures correctly positions the valve 200 and centering the suturesbetween the commissure posts is the most accessible for tying knotsbecause the cusps are the lowest points in the annulus. Placement ofknots (or clips) at the lowest point in the annulus also helps minimizethe risk of coronary occlusion.

A more detailed understanding of the unitary heart valve 200 and holder206 follows with reference to FIGS. 14-19. With reference to FIGS. 14and 15, the heart valve 200 including the prosthetic valve 208 andcoupling stent 202 is shown attached to the holder 206, while the holderis shown by itself in FIG. 16. The assembly is also seen in FIGS.17A-17E.

As explained above, the prosthetic valve 208 has three flexible leaflets210 supported by a non-expandable, non-collapsible annular supportstructure 212 and a plurality of commissure posts 214 projecting in anoutflow direction, with a suture-permeable ring 216 circumscribing aninflow end thereof. In one embodiment, the heart valve 200 is acommercially available, non-expandable prosthetic heart valve 208 havinga sewing ring 216, such as a Carpentier-Edwards PERIMOUNT Magna AorticBioprosthesis valve, attached to a pre-crimped tapered Stainless Steelcoupling stent 202 lined and/or covered by a fabric (e.g., Dacron) skirt218, as seen in FIG. 15. An external fabric cover or sleeve is shownbelow with reference to the detailed stent drawings of FIGS. 18-19.

As seen in FIG. 16, the holder 206 includes a central tubular bodyhaving the downwardly-directed boss 226 on the lower end, an upwardlydirected hub 227 on the upper end, a narrow tubular section 228 belowthe hub, and section with three outwardly-directed anchoring fingers 229(see FIG. 14). A continuous cylindrical lumen extends the length of theholder 206 from top to bottom for passage of the distal end of theballoon catheter 260, as mentioned above. The fingers 229 includeanchoring structure as will be described that permits attachment to eachof the upstanding commissure posts 214 on the prosthetic valve 208.

FIG. 16 illustrates the downwardly-directed boss 226 having externalthreading for mating with the leaflet parting sleeve 204. Three gaps 231separate the boss 226 from downwardly-extending portions of eachanchoring finger 229 and provide annular clearance for the tubularsleeve 204. Small ratchet teeth 232 provided on an inner surface of eachanchoring finger 229 contact the exterior of the parting sleeve 204, andpreferably a roughened portion thereof, and provide an anti-rotationfriction to secure the sleeve on the boss. The teeth 232 are eachcantilevered inward in a clockwise direction looking from the bottom soas to permit the sleeve 204 to easily screw on but present resistance tounscrewing the sleeve in a counter-clockwise direction.

Each anchoring finger 229 includes a generally flat lower face 233bordered on an outer edge by a downwardly-extending U-shaped rail 234. Aplurality of through holes 235 extend axially through each finger 229 toan upper surface, as seen in FIG. 17D. In particular, a first pair ofthrough holes 235 a opens radially inward from an upper cutting guide236, and a second pair of through holes 235 b opens radially outwardfrom the cutting guide. As seen best in FIG. 15, the tip of eachcommissure post 214 contacts the lower face 233 of one of the anchoringfingers 229 within the U-shaped rail 234. The commissure post 214 ispreferably fabric-covered, or otherwise suture-permeable, and a suture(not shown) is used to secure the post 214 to the underside of theanchoring finger 229. The suture passes through the first and secondpairs of through holes 235 a, 235 b such that a mid-portion extendsacross spaced notches 237 in the cutting guide 236 (see FIG. 17D again).By securing the free ends of the suture to the holder 206, such as onthe underside of the fingers 229, a scalpel may be used to sever themid-portion that extends across a cutting well 238 in the cutting guide236 to release the commissure post 214 from the holder. Severing allthree sutures releases the prosthetic valve 208 from the holder 206.

FIGS. 17A-17F illustrate a preferred suture-permeable ring 216circumscribing an inflow end of the prosthetic valve 208. The ring 216defines a relatively planar upper face 239 and an undulating lower face241. Cusps of the annular support structure 212 abut the upper face 239opposite locations where the lower face 241 defines peaks. Conversely,the valve commissure posts 214 align with locations where the lower face241 defines troughs. The undulating shape of the lower face 241advantageously matches the anatomical contours of the aortic side of theannulus AA, that is, the supra-annular shelf. The ring 216 preferablycomprises a suture-permeable material such as rolled synthetic fabric ora silicone inner core covered by a synthetic fabric. In the latter case,the silicone may be molded to define the contour of the lower face 241and the fabric cover conforms thereover.

The coupling stent 202 (shown separated in FIGS. 18-19) preferablyattaches to the suture-permeable ring 216 during the manufacturingprocess in a way that preserves the integrity of the ring and preventsreduction of the valve's effective orifice area (EOA). Desirably, thecoupling stent 202 will be continuously sutured to the ring 216 in amanner that maintains the contours of the ring. In this regard, suturesmay be passed through apertures or eyelets 243 arrayed along an upper orfirst end 245 of the stent 202. Other connection solutions includeprongs or hooks extending inward from the stent, ties, Velcro, snaps,adhesives, etc. Alternatively, the coupling stent 202 may be morerigidly connected to rigid components within the prosthetic valve 208.

The plastically-expandable coupling stent 202 is seen in greater detailin a contracted state in FIGS. 18A-18C, and in an expanded state inFIGS. 19A-19D. The general function of the stent 202 is to provide themeans to attach the prosthetic valve 208 to the native aortic root. Thisattachment method is intended as an alternative to the present standardsurgical method of suturing aortic valve bio-prostheses to the aorticvalve annulus, and is accomplished in much less time. Further, thisattachment method improves ease of use by eliminating most of not allsuturing.

Device attachment to the native valve structure is achieved using aballoon catheter to expand and deploy the stent covered by a fabric(e.g., Dacron) skirt 218. In the views of FIGS. 17F and 18-19, thefabric skirt 218 surrounds the outside of the stent 202, and is shown inphantom, but may also be provided on the inside of the stent. The mainfunctions of this sleeve 218 are to help prevent paravalvular leaks andprovide means to securely encapsulate any Calcium nodules on the aorticvalve leaflets (if left in place) and/or the aortic valve annulus.

As best seen in FIG. 17F, a preferred embodiment of the valve 200includes a fabric sleeve 218 covering the entire inflow coupling stent202 with a combination of PTFE knit cloth on the ID, ends and part ofthe OD. The part of the OD closest to the sewing ring 216 is alsocovered with a PET knit cloth to seal leaks. Covering the entirecoupling stent 202 eliminates exposed metal and decreases the risk ofthromboembolic events and abrasion.

The stent 202 may be similar to an expandable Stainless Steel stent usedin the Edwards SAPIEN Transcatheter Heart Valve. However, the materialis not limited to Stainless Steel, and other materials such as Co—Cralloys, etc. may be used.

FIGS. 18A-18C show the stent 202 in its pre-crimped taperedconfiguration that facilitates insertion through the calcified nativeaortic valve (see FIG. 13C). The stent lower edge 222 describes a circlehaving a smaller diameter than a circle described by the upper or firstend 245. The upper end 245 follows an undulating path with peaks andtroughs that generally corresponds to the undulating contour of theunderside 241 of the suture-permeable ring 216 (see FIG. 15). Themid-section of the stent 202 is somewhat similar to the stent 140 seenin FIG. 12B, and has three rows of expandable struts 246 in a sawtoothpattern between axially-extending struts 247, and a thicker wire upperend 245. The axially-extending struts 247 are in-phase with the peaksand troughs of the upper end 245 of the stent. The reinforcing ringdefined by the upper end 245 is continuous around its periphery and hasa substantially constant thickness or wire diameter interrupted by theaforementioned eyelets 243.

The minimum I.D. of the upper end 245 of the covered stent 202 willalways be bigger than the I.D. of the prosthetic valve 208 to which itattaches. For instance, if the upper end 245 secures to the underside ofthe suture-permeable ring 216, which surrounds the support structure 212of the valve, it will by definition be larger than the I.D. of thesupport structure 212.

FIGS. 19A-19C show the stent 202 in its expanded configuration thatanchors the heart valve 200 to the calcified native aortic valve (seeFIG. 13K). The stent lower end 222′ is seen in FIG. 19C expanded fromits contracted dimension of FIG. 18C. Note that the shape is notprecisely circular, and use of the term “diameter” to define thecontracted and expanded sizes is necessarily approximate. As will beexplained below, the procedure desirably incorporates a shaped expansionballoon 262 that expands the stent 202 from its initial conical shape ofFIG. 18A to its final conical shape of FIG. 19A. In the expansion step,the balloon 262 primarily exerts greater outward force on the lowerportions of the stent 202, so that the upper end 245 remainssubstantially the same. This prevents distortion of the suture-permeablering 216 to which the stent 202 attaches.

It should be noted that a plastically-expandable stent 202 desirablyprovides sufficient anchoring force for the heart valve 200, and alsopermits some expansion of the annulus itself. That said, aself-expanding material may be used, though such a stent would likelyrequire supplemental coupling means, such as barbs, staples, etc.

FIGS. 20A-20C show a system 300 for delivering the unitary heart valve200 of FIGS. 14-17. The delivery or deployment system 300 consists of atwo-piece handle, wherein one piece is removable and hollow and used asa handle interface with the bio-prosthesis.

The system 300 in FIGS. 20A-20C is illustrated with the prosthetic valve208 attached to the holder 206, but omits the coupling stent 202 forclarity in viewing and understanding the function of the balloon 262.The system 300 includes the aforementioned balloon catheter 260 whichcommences on a proximal end with a Y-fitting 302 and terminates at adistal tip 304. The balloon catheter 260 extends the entire length ofthe system 300 and will be described further below with reference toFIGS. 24A-24D. The entire system preferably has a length L from theproximal end of the Y-fitting 302 to the distal tip 304 of between about100 and 500 mm.

The present application describes an essentially rigid delivery systemin that the handle 306 is preferably made of rigid polymer such aspolypropylene. An alternative system contemplates a flexible deliverysystem that may be bent out of the way and have a length of up to 800mm. The diameter of such a delivery system will not be as small asprevious percutaneous devices, as the primary access route is through adirect access pathway and small diameters are not necessary.

The system 300 also includes a two-piece handle assembly 306 thatcombines the aforementioned distal section 240 mated with the proximalsection 244. The handle components are further described with referenceto FIGS. 21 and 22. The length l of the handle 306 is preferably betweenabout 150 and 300 mm. The Y-fitting 302 connected in series to theproximal handle section 244, which in turn couples to the distal section240 attached to the holder 206. A through lumen extends the length ofthese connected components for sliding passage of the balloon catheter260 such that the balloon 262 may extend through the prosthetic valve208. The connections between the components comprise concentric tubularcouplings wherein a distal tube fits within a proximal tube to reducethe chance of snagging the balloon 262 as it travels therethrough.

FIG. 21 is an elevational view of the delivery system 300 of FIGS.20A-20C including the coupling stent 202, while FIG. 22 shows thecomponents exploded, but without the balloon catheter 260, valve 200 andholder 206. The distal and proximal handle sections 240, 244 includesnap-fit couplers 310 on their mating ends in the form of cantileveredteeth that snap into complementary recesses formed in respectivereceiving apertures (one of which is on the hub 227 of the valve holder206). Of course, threading on the mating parts could also be used, aswell as other similar expedients. The distal handle section 240 includesa proximal grip 312 that facilitates manipulation of the heart valve 200when attached thereto. Likewise, the proximal handle section 244 has anexterior grip 314 to enable a user to easily couple and decouple it withrespect to the adjacent components, and also to provide continuity withthe distal section grip 308.

FIG. 21 shows the balloon 262 inflated to expand the valve couplingstent 202, while FIGS. 23 and 24A-24D show the preferred shape of theballoon 262. As mentioned, the final or expanded shape of the couplingstent 202 is frustoconical, and the balloon 262 includes an up-taperedmiddle segment 320 that contacts the coupling stent 202. The middlesegment 320 has the same or a slightly greater included taper angle θ toaccount for material rebound. As seen in FIG. 24D, the taper angle θ ispreferably between about 0-45°, and more preferably is about 38° (0°being a cylindrical expansion). A short proximal lead-in up-taper 322and a distal down-taper 324 flank the up-tapered middle segment 320.Alternatively, the balloon 262 may include curves or non-axi-symmetriccontours to deform the coupling stent 202 to various desired shapes tofit better within the particular annulus. Indeed, various potentialshapes are described in U.S. Patent Publication 2008-0021546, entitledSystem for Deploying Balloon-Expandable Heart Valves, published Jan. 24,2008, the disclosure of which is expressly incorporated herein.

In use, the prosthetic heart valve 200 (or valve 30) is selected basedon type and size. Typically, the heart valve 200 includes bioprostheticleaflets, such as bovine pericardium leaflets, and remains stored in apreservative solution in a contaminant-free jar. If the holder 206attaches to the valve with sutures, as preferred, the holder alsoresides in the jar during storage and shipping.

After the surgeon stops the heart and exposes and measures the annulusfor size, he/she selects a valve size that is larger than the annulus.Technicians open the jar containing the selected valve and snap thedistal handle section 240 into the holder hub 227 while the combinationof the heart valve 200 and holder 206 is still in the jar. The resultingassembly facilitates handling of the bio-prosthesis during pre-procedurepreparations (i.e. rinsing steps, etc.). The grip 312 on the distalhandle section 240 facilitates these preparation steps.

The surgeon places guiding sutures 230 into the annulus at the cusplocations, and then back out and through the valve sewing ring in thecorresponding locations. The surgeon slides the valve down the guidingsutures 230 using the distal end 240 of the handle assembly 306 to pressthe valve into position within the annulus, as seen in FIG. 13C. Theguiding sutures 230 facilitate rotational and axial positioning of thevalve 200 so the valve does not block the coronary ostia and sits downagainst the top of the annulus, as seen in FIG. 13D. After the valve 200is secured in position by the guiding sutures 230 and snares 250, as inFIG. 13E, the surgeon places the balloon catheter 260 (see FIG. 13F)through the distal section 240 and locks it into position using theproximal section 244, as shown in FIG. 13G. The surgeon then inflatesthe balloon 262, as shown in FIG. 13H, expanding the coupling stent 202which expands the annulus and secures the valve 200 in the correctposition. After balloon deflation, as shown in FIG. 13I, the surgeonseparates the holder 206 from the valve 200, and withdraws the holder,handle assembly 306, and balloon catheter 260 from the patient using thegrips 312, 314 (see FIG. 22) on the handle.

In the case of the first embodiment, where the unitary heart valve 30mounts on a balloon catheter 32, the proximal section 62 thatincorporates the balloon 40 pre-assembled in its central lumen snapsonto the distal section 64 to form the hollow handle 60. As both handlepieces are snapped together, the balloon catheter with its wrappedballoon is encapsulated in the handle shaft formed by the two matinghandle pieces.

The delivery system 300 provides two positions for the balloon catheter:

i. A retracted balloon position used at the pre coupling stentdeployment stage of the procedure.

ii. An advanced balloon position used for coupling stent deployment. Theadvanced position is used once the heart valve 200 has been placed inthe desired aortic root position and balloon expansion is required toexpand the coupling stent and secure the implant in place.

When proper placement of the valve 200 is insured, the surgeon inflatesthe balloon 262 using saline or similar expedient to its maximum size,or with a predetermined volume of inflation fluid. This expands thecoupling stent 202 to its implant size against the annulus (orleaflets). Thereafter, the balloon 262 is deflated and removed fromwithin the heart valve 200. Upon completing deployment, the valve holdersutures are cut with a scalpel and the delivery system 300 retractedthrough valve leaflets to complete the deployment procedure.

In another advantageous feature, the two-component valve systemillustrated in the preceding figures provides a device and method thatsubstantially reduces the time of the surgical procedure as comparedwith replacement valves that are sutured to the tissue after removingthe native leaflets. For example, the coupling stent 36, 202 may bedeployed quickly such that the heart valve 200, 30 may be rapidlyattached to the annulus. This reduces the time required onextracorporeal circulation and thereby substantially reduces the risk tothe patient.

In addition to speeding up the implant process, the present inventionhaving the valve and its robust plastically-expandable stent, permitsthe annulus to be expanded to accommodate a larger valve than otherwisewould be possible. In particular, clinical research has shown that theleft ventricular outflow tract (LVOT) can be significantly expanded by aballoon-expandable stent and still retain normal functioning. In thiscontext, “significantly expanding” the LVOT means expanding it by atleast 5%, more preferably between about 5-30%, and typically between10-20%. In absolute terms, the LVOT may be expanded 1.0-5 mm dependingon the nominal orifice size. This expansion of the annulus creates anopportunity to increase the size of a surgically implanted prostheticvalve. The present invention employs a balloon-expandable valve stentwhich permits expansion of the LVOT at and just below the aorticannulus, at the inflow end of the prosthetic valve. The interference fitcreated between the outside of the coupling stent and the LVOT securesthe valve, desirably without pledgets or sutures taking up space,thereby allowing for placement of the maximum possible valve size. Alarger valve size than would otherwise be available with conventionalsurgery enhances volumetric blood flow and reduces the pressure gradientthrough the valve.

It will be appreciated by those skilled in the art that embodiments ofthe present invention provide important new devices and methods whereina valve may be securely anchored to a body lumen in a quick andefficient manner. Embodiments of the present invention provide a meansfor implanting a prosthetic valve in a surgical procedure with as few asthree sutures rather than the 12-24 sutures typically used for aorticvalve replacement. Accordingly, the surgical procedure time issubstantially decreased. Furthermore, in addition to providing acoupling stent for the valve, the stent may be used to maintain thenative valve in a dilated condition. As a result, it is not necessaryfor the surgeon to remove the native leaflets, thereby further reducingthe procedure time.

It will also be appreciated that the present invention provides animproved system wherein a valve member may be replaced in a more quickand efficient manner. More particularly, it is not necessary to cut anysutures in order to remove the valve. Rather, the valve member may bedisconnected from the coupling stent and a new valve member may beconnected in its place. This is an important advantage when usingbiological tissue valves or other valves having limited design lives.

The variations on quick-connect heart valves, systems and methods maychange based on surgeon preferences, empirical testing, economies, etc.Several possible variations include:

-   -   A stent frame that provides attachment means and also prevents        native, calcified leaflets to interfere with flow.    -   A secondary piece mounted on the aortic side of the suturing        ring to help improve attachment.

The present application encompasses numerous ways to couple theprosthetic valve 208 to the coupling stent 202, as mentioned above.However, a preferred version includes attaching the coupling stent 202to the inflow end of valve 208 with sutures, as will be described withreference to FIGS. 25-28.

FIG. 25A shows the valve 208 slightly separated above the coupling stent202 with a first temporary suture 350 connected therebetween. The firsttemporary suture 350 includes a triple wrap loop with suture material(e.g., P/N 400830001) which passes downward from the top of the sewingring 216, at the center of the commissure 214, between the sewing ringand synthetic support structure 212 (e.g., Elgiloy band, not shown) ofthe valve 208. The needle 352 threads down through the sewing ring 216toward inflow end of the valve 208, through a commissure hole 354 on thecoupling stent 202 (shown schematically in FIG. 25B) to the inside ofthe stent, and back upward through the sewing ring 216 through thetriple wrap loop to be tightened. The technician then makes onebackstitch on the rolled tab on the stent 202 and trims the loose endsoff. Three such temporary sutures 350 are installed at the threecommissures of the valve 208. These three sutures are used to positionthe stent 202 below the valve 208 while permanent sutures are installed.

Note that in this version the upper end 245 of the stent 202 follows anundulating path with peaks and troughs that generally corresponds to theundulating contour of the underside of the sewing ring 216. Therefore,the temporary sutures 350 ensure that the peaks of the upper end 245 ofthe stent 202 match the troughs of the sewing ring 216, which arelocated under the commissures 214 of the valve.

FIGS. 26A-26D illustrate several initial steps in an exemplaryinstallation of permanent sutures 360. Preferably, the technician cuts alength of suture material (e.g., PTFE thread, P/N 491176003)approximately 30 inches long and double threads a needle 362. Startingat a commissure center, and between the sewing ring and Elgiloy band,place the needle 362 down through the sewing ring 216 toward inflow end.Go through the commissure hole 354 on the coupling stent 202 (FIG. 25B)to the inside of the stent and back up through the sewing ring 216,through the suture loop 364 and tighten. Go back down through sewingring 216, catch the stent 202 between the commissure strut hole 354 andthe next vertical strut hole 356 (FIG. 25B), to the inside of the stentand back up through the sewing ring to catch the previous stitch andtighten. Once the next commissure hole is reached, remove the temporarystitch 350.

Continue the stitches at every stent hole and the between every stenthole making 36 stitches, as illustrated in FIGS. 27 and 28. In theillustrated embodiment, the stent 202 has eighteen holes along the upperend 245, three commissure holes 354 at the peaks and five intermediateholes 356, as seen in FIG. 25B. Of course, the stent 202 may have moreor less holes, or no holes, though the holes provide secure anchorages,clear spacing, and good targets for the assembly technician. Thetechnician completes the stitch by passing the suture 360 through thestarting commissure hole again, catching the first stitch and making asingle lock knot. The suture 360 is then moved to the rolled tab on thestent 202 and another double-spaced single lock knot is made. Thetechnician buries the suture 360 and cuts the thread. No gap is leftbetween the stitches on the sewing ring 216 area, as seen in FIG. 29. Nogap is left between sewing ring 216 and the stent 202.

While the invention has been described in its preferred embodiments, itis to be understood that the words which have been used are words ofdescription and not of limitation. Therefore, changes may be made withinthe appended claims without departing from the true scope of theinvention.

1. A prosthetic heart valve for implant at a heart valve annulus,comprising: a non-expandable, non-collapsible annular support structuredefining a flow orifice and having an inflow end; valve leafletsattached to the support structure and mounted to alternately open andclose across the flow orifice; a suture-permeable ring circumscribingthe inflow end of the support structure; and a plastically-expandablecoupling stent having a first end extending around the flow orifice andconnected to the valve at the inflow end of the support structure, thecoupling stent having a second end projecting in the inflow directionaway from the support structure and being capable of assuming acontracted state for delivery to an implant position and an expandedstate wider than the first end for outward contact with an annulus. 2.The system of claim 1, wherein the support structure includes aplurality of commissure posts projecting in an outflow direction, andthe valve leaflets are flexible and attach to the support structure andcommissure posts.
 3. The system of claim 1, wherein the suture-permeablering is a sewing ring, and wherein the coupling stent attaches to thesewing ring.
 4. The system of claim 1, wherein in the contracted statethe coupling stent is conical, tapering inward from the first end towardthe second end.
 5. The system of claim 4, wherein in the expanded statethe coupling stent is conical, tapering outward from the first endtoward the second end.
 6. The system of claim 5, wherein the couplingstent comprises a plurality of radially expandable struts at least someof which are arranged in rows, and wherein the distalmost row has thegreatest capacity for expansion from the contracted state to theexpanded state.
 7. The system of claim 1, wherein the prosthetic valvecomprises a commercially available valve and the suture-permeable ringis a sewing ring thereof having the plastically-expandable couplingstent connected to the sewing ring.
 8. A method of delivery and implantof a prosthetic heart valve system, comprising: providing a heart valveincluding a prosthetic valve having a non-expandable, non-collapsibleorifice, the heart valve further including an expandable coupling stentextending from an inflow end thereof, the coupling stent having acontracted state for delivery to an implant position and an expandedstate configured for outward connection to the annulus; advancing theheart valve with the coupling stent in its contracted state to animplant position adjacent the annulus; and expanding the coupling stentto the expanded state in contact with and connected to the annulus. 9.The method of claim 8, further including mounting the heart valve on aholder having a proximal hub and lumen therethrough, and mounting theholder on the distal end of a handle having a lumen therethrough, themethod including passing a balloon catheter through the lumen of thehandle and the holder and within the heart valve, and inflating aballoon on the balloon catheter to expand the coupling stent.
 10. Themethod of claim 9, further including packaging the heart valve mountedon the holder separately from the handle and the balloon catheter. 11.The method of claim 9, wherein the contracted state of the couplingstent is conical, and wherein the balloon on the balloon catheter has alarger distal expanded end than its proximal expanded end so as to applygreater expansion deflection to the coupling stent than to theprosthetic valve.
 12. The method of claim 8, wherein the contractedstate of the coupling stent is conical, and wherein the coupling stentcomprises a plurality of radially expandable struts at least some ofwhich are arranged in rows, and wherein the row farthest from theprosthetic valve has the greatest capacity for expansion from thecontracted state to the expanded state.
 13. The method of claim 8,wherein the coupling stent comprises a plurality of radially expandablestruts, and a row farthest from the prosthetic valve has alternatingpeaks and valleys, and the method includes expanding the distal end ofthe coupling stent more than the rest of the coupling stent so that thepeaks in the row farthest from the prosthetic valve project outward intothe annulus.
 14. The method of claim 8, including increasing the orificesize of the heart valve annulus by 1.0-5 mm by plastically expanding thecoupling stent.
 15. The method of claim 14, wherein the prosthetic valveof the valve component is selected to have an orifice size that matchesthe increased orifice size of the heart valve annulus.
 16. A system fordelivering a prosthetic heart valve, comprising: a heart valve includinga prosthetic valve having a non-expandable, non-collapsible orifice, theheart valve further including an expandable coupling stent extendingfrom an inflow end thereof, the coupling stent having a contracted statefor delivery to an implant position and an expanded state; a valveholder connected to a proximal end of the heart valve; a ballooncatheter having a balloon; and a handle configured to attach to aproximal end of the valve holder and having a lumen for passage of thecatheter, the balloon extending distally through the handle, past theholder and through the heart valve.
 17. The system of claim 16, whereinthe prosthetic valve comprises a commercially available valve having asewing ring, and wherein the coupling stent attaches to the sewing ring.18. The system of claim 16, wherein the contracted state of the couplingstent is conical, tapering down in a distal direction.
 19. The system ofclaim 16, wherein the contracted state of the coupling stent is conicaland tapers down in a distal direction, and wherein the balloon catheterfurther includes a generally conical nose cone on a distal end thereofthat extends through the heart valve and engages a distal end of thecoupling stent in its contracted state.
 20. The system of claim 16,wherein the handle comprises a proximal section and a distal sectionthat may be coupled together in series to form a continuous lumen, andwherein the distal section is adapted to couple to the hub of the holderto enable manual manipulation of the heart valve using the distalsection prior to connection with the proximal handle section.
 21. Thesystem of claim 20, wherein the balloon catheter and proximal handlesection are packaged together with the balloon within the proximalsection lumen.
 22. The system of claim 16, wherein the heart valvemounted on the holder is packaged separately from the handle and theballoon catheter.